For questions about the functionality related to permutations in Mathematica.
9
votes
4answers
199 views
Efficient way to turn a subset into a permutation
For an input vector $\{a_1,a_2,\ldots,a_n,b_{1},b_2,\ldots,b_{m}\}$ and a list of ordered positions $\{k_1,k_2,\ldots, k_n\}$, such that $1\leqslant k_1 < k_2 < \ldots < k_n \leqslant ...
9
votes
2answers
203 views
Combining nested lists that meet certain criteria for a permutation
I have the following list representing a permutation on 26 characters:
...
8
votes
3answers
358 views
How to remove repeated permutations?
I want to get the Permutations on the elements of a list. Then I'm doing this:
...
8
votes
2answers
220 views
How to represent a list as a cycle
I want to select distinct cycles (represented by List).
The cycle {a, b, c, d} must be the same as {b, c, d, a} or ...
8
votes
3answers
209 views
Reduce the output from tuples by including symmetry?
I need all the possible 3x3 binary tensors, but I'd like to have this account for symmetries. I've started by using the Tuples command.
Tuples[{1, 0}, {3, 3}]
...
8
votes
0answers
178 views
Using Compile to speed up Function with PermutationProduct
I have the following fairly simple routine dot involving PermutationProduct that I wish to speed up using ...
7
votes
1answer
482 views
How to apply a permutation to a symmetric square matrix?
Given a symmetric square matrix, how can I apply a permutation to the rows and columns (i.e. the same permutation to both the rows and the columns) such a way that the new structure of the matrix ...
7
votes
1answer
196 views
Mathematica function/package for shuffle permutations
Does anyone knows a way to compute a list of all (p,q)-shuffles in mathematica?
For a definition of the shuffle permutations see for example http://ncatlab.org/nlab/show/shuffle
I'm dreaming of a ...
6
votes
2answers
136 views
Find all permutations with a condition
How can I find all the permutations of {a, b, c} where a + b + c = n?
For instance: if ...
2
votes
1answer
240 views
Adding rules to permutations
How can I calculate only those permutations of Range[n], that satisfy certain rules?
I don't want to filter the result after calculating all the permutations but ...
1
vote
1answer
163 views
How can I permute a multiset?
I have a multiset {1, 3, 3, 1, 2} and would like to randomly permute the classes like so: {2, 1, 1, 2, 3} or {3, 2, 2, 3, 1}, what is the simplest and most efficient way to do this?
In reality the ...
0
votes
0answers
4 views
permutation and abstarct-algebraShow that there does not exist a permutation α in S4 satisfying (1 2)(3 4)α = α(1 2 3 4)? [closed]
Show that there does not exist a permutation α in S4 satisfying (1 2)(3 4)α = α(1 2 3 4)?
-2
votes
0answers
62 views
How many combinations are there with a 4-digit pin? [closed]
A pin can be any number between 0000 and 9999. So I'm guessing there are 10,000 combinations.
But I also read somewhere that you calculate by doing 4*3*2*1 = 24.
Since you can re-use numbers, I ...
